Study On Control Of Handover Pier Deviation Of Continuous Beam Bridge With Large Longitudinal Slope And Flexble High Piers

In recent years, with the penetration of our national westen development strategy, highways in central and western regions have been developed unprecedentedly. The terrain of the west areas are mainly plateau, basin and mountain land, and the geological conditions are quite complex. The horizontal and vertical alignment of highway bridges in mountain areas are extrenmly prominent affected by the local terrain. Curve, large longitudinal slope and high pier become the distinguishing features of highway bridges in mountain areas.The disease of handover pier deviation on continuous beam bridge with large longitudinal slope and flexible high piers have appeared in many mountain highways, nearly becoming a universal problem. At present, researches on this problem.are less both at home and abroad, and the given reasons of this problem have not been unified yet. Besides, researches on treatment methods after diseases generated are also few. The thesis takes Hongyang Bridge as background, which appeared this kind of disease at one highway, and it conducts detailed study on the causes of handover pier deviation disease, the safety of disease piers, the construction and construction monitoring of reflecting deviated handover piers.First of all, it set up whole bridge finite element model, then it made an analysis on forming process of deviation disease according to three stages including the simply supported beam system, the simply-supported continuous beam and construction vehicle passage. The outcome shows that the out-of-level on bearing installation is the primary cause that leads to the deviation of bridge pier, and the dead load, live load of superstructure as well as temperature load acting on out-of-level bearings even worsen the situation.In order to study the effect that pier deviation has on performance of a bridge, the thesis compiled a full-range nonlinear analysis program to test the loaded property of bridge piers, evaluated piers'mechanical deformation state under deviation, and analyzed its compressive bearing capacity and finished checking calculation again after correction and reinforcement.From the perspective of disease treatment, this thesis rectified deviations and strengthened the piers of Hongyang Bridge and implemented construction monitoring during overall process. Besides, it respectively implemented continuous monitoring and long-term monitoring on the piers after rectification and strengthening. During the process of deviation rectification, the superstructure basically remained immobile, the loading state of bridge piers was even, and the structure was safe. After the rectification was completed, the piers'verticality and width of expansion joints have periodical changes according to the temperature, and the working condition of piers and bearings were good. The deviation rectification and strengthening of piers have achieved favorable effect.The author analyzed the main reasons accounting for the disease of handover pier deviation on continuous beam bridge with large longitudinal slope and flexible high piers and its effec on performance of a bridge through the analysis of the causes that account for the handover piers deviation of Hongyang Bridge, the nonlinear analysis testing the loaded property of bridge piers and the construction monitoring on rectification of piers deviation. Valuable conclusions were obtained and effective treatment and suggestions were also put forward to provide a reference for the similar engineering disease treatment.